The Holophonor is a musical instrument in the 31st century and a kind of combination between an oboe and a holographic projector. The music played triggers the projector to show matching holographic pictures. Therefore, the instrument requires great skill to be played properly, and only a few people in the whole universe manage some skill in it. Apparently, they are not very good at it.

The instrument is, as it were, instrumental for the plot of two episodes, "Parasites Lost" and "The Devil's Hands Are Idle Playthings". In the first episode, the parasitic worms that improved Fry enabled him to play the Holophonor perfectly, which in turn allowed him to win Leela's heart. When he made the worms leave, his new skill was gone and Leela dumped him, most likely because she suspected it was in fact what the worms had made of him rather than Fry that she loved. After this, he tried to reacquire his skill with the instrument, only succeeding when he made a deal with the Robot Devil, becoming a famous player for a short time.